Gliese 581g is the first planet other than Earth to exist within its star's habitable zone, meaning it could support human life. Now we've got an idea of what it looks like...and it's seriously spooky. »1/20/11 11:29am 1/20/11 11:29am

It's not a fun question to ask, but anytime a discovery of this magnitude comes along, it's a good idea to hang on to a little skepticism. So let's sort through the biggest questions about Earth's newly discovered sibling. »10/15/10 12:55pm 10/15/10 12:55pm

Due to their position in the Gliese system, hypothetical creatures on planet Zarmina might not be alone in their own solar system, the way humans seem to be. And those neighbors could reach Zarmina pretty quickly. »10/14/10 7:00am 10/14/10 7:00am

That's what one scientist is claiming, saying he detected a suspicious light pulse in the vicinity of Gliese 581g two years ago. But the rest of the astronomy community is blasting his claims, accusing him of making a mistake...or worse. »10/11/10 5:00pm 10/11/10 5:00pm

It's been a century since we established the first colony on planet Zarmina, in the Gliese system 20 light years from Earth. After scientists discovered its oxygen-rich atmosphere, it wasn't long before settlers came. And then tourists, and hockey teams. »10/06/10 8:30am 10/06/10 8:30am

Using our current technology, it would take 180,000 years to reach Zarmina. But our resident physicist Dave Goldberg has a more optimistic estimate - thanks to antimatter and time dilation, astronauts could get there in just a few years. »10/05/10 1:00pm 10/05/10 1:00pm

Steve Vogt is the UC Santa Cruz astrophysicist who discovered Zarmina, the first recorded Earthlike planet outside our solar system. He told io9 what a human colony there would be like, and why he believes the planet already harbors life. »10/01/10 1:36pm 10/01/10 1:36pm

Orbiting a nearby red dwarf star called Gliese 581 are 6 planets. One of them is a rocky ball, bigger than Earth, in the "habitable zone" where water is liquid and temperatures are human-friendly. It's possible we could live there. »9/29/10 5:19pm 9/29/10 5:19pm